package com.fuzongle.tank.test;

import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.web.servlet.i18n.SessionLocaleResolver;

import javax.servlet.http.HttpServletRequest;
import java.util.Locale;

/**
 * @Auther: fuzongle
 * @Date: 2020/6/11 21:07
 * @Description:
 */

public class SpringContextUtil implements ApplicationContextAware {
    private static ApplicationContext applicationContext;

    /**
     * 实现ApplicationContextAware接口的context注入函数, 将其存入静态变量.
     */
    public void setApplicationContext(ApplicationContext applicationContext) {
        SpringContextUtil.applicationContext = applicationContext;
    }

    /**
     * 取得存储在静态变量中的ApplicationContext.
     */
    public static ApplicationContext getApplicationContext() {
        checkApplicationContext();
        return applicationContext;
    }

    /**
     * 从静态变量ApplicationContext中取得Bean, 自动转型为所赋值对象的类型.
     */
    @SuppressWarnings("unchecked")
    public static <T> T getBean(String name) {
        checkApplicationContext();
        return (T) applicationContext.getBean(name);
    }

    /**
     * 从静态变量ApplicationContext中取得Bean, 自动转型为所赋值对象的类型.
     */
    @SuppressWarnings("unchecked")
    public static <T> T getBean(Class<T> clazz) {
        checkApplicationContext();
        return (T) applicationContext.getBeansOfType(clazz);
    }

    private static void checkApplicationContext() {
        if (applicationContext == null)
            throw new IllegalStateException("applicaitonContext未注入,请在spring-mvc.xml中定义SpringContextUtil");
    }

    public static String getMessage(String key, HttpServletRequest request) {
        return applicationContext.getMessage(key, null, getLocal(request));
    }

    public static String getMessage(String key, String[] args, HttpServletRequest request) {
        return applicationContext.getMessage(key, args, getLocal(request));
    }

    public static Locale getLocal(HttpServletRequest request) {
        Locale locale = (Locale) request.getSession().getAttribute(SessionLocaleResolver.LOCALE_SESSION_ATTRIBUTE_NAME);
        if (locale == null) {
            locale = request.getLocale();
        }

        return locale;
    }
}

